Daniel Cormier says he tested positive for COVID-19 as UFC title fight with Stipe Miocic neared

Daniel Cormier explains decision to retire (1:25)

Daniel Cormier tells Ariel Helwani why he won't continue fighting after his UFC 252 bout vs. Stipe Miocic. (1:25)

Daniel Cormier tested positive for COVID-19 less than six weeks before his UFC heavyweight title fight with Stipe Miocic, Cormier confirmed to ESPN on Tuesday.

Cormier said one of his training partners tested positive for the coronavirus on July 1, prompting the entire team to get tested. In that test, he was negative. But a week later, Cormier started to feel sick. He got tested again July 8 and the result that time was positive.

If not for a smart ring he has been wearing, Cormier said he might not have gotten the second test -- and he likely would have pushed through without dialing back his training despite not feeling well. Cormier said he doesn't know if he would have even made the fight, which was Aug. 15 in Las Vegas, had he not taken his training down a notch when he did.

"I'd have kept training, not knowing I was sick, running the risk of infecting everybody else -- infecting the entire gym," Cormier said. "You also don't know what your experience with the virus is going to be if you continue to run yourself down physically. Then it's just attacking my immune system. I took the data and those warning signs from the ring and I applied them."

The Oura ring, which connects to smartphones via Bluetooth, gives regular readings on sleep, health and performance. The UFC announced Tuesday that it had partnered with Oura Health and would be sending rings to fighters who want one.

Cormier said he saw drastic changes in his numbers as he began to feel sick. His resting heart rate went from 50 to 70. His heart rate variability plummeted from 70 to 23. And his body temperature rose almost 2 degrees. So, despite the negative COVID-19 test initially, he got tested again and slowed down his training.

"All those numbers that I was paying such close attention to were telling me that something wasn't right," said Cormier, who ended up losing the bout to Miocic by unanimous decision. "It didn't tell me I had COVID. But it told me something wasn't right."

When Cormier found out he had COVID-19, he took the next day off from training. He had already been training in his garage and quarantining away from his family, including his pregnant wife, in another part of his Gilroy, California, home.

But Cormier said one of his coaches, who had COVID-19 previously, was willing to hold pads for him. So he did that for two days. In the meantime, he reached out to physician friends, who directed him to a top San Francisco Bay Area infectious disease doctor. The doctor gave him medication, and in a few days he started to feel better. His other training partners, Cormier said, were willing to continue despite the risks.

Cormier, 41, said he got a call from a Santa Clara County official following the positive test, telling him he had to quarantine for 14 days. The former UFC heavyweight and light heavyweight champion said he felt he followed the rules and kept his garage training camp like a bubble. Cormier said he spent more than $5,000 on coronavirus testing for himself, coaches and training partners during his camp.

"I'm training in my garage," Cormier said. "I'm staying at home. I'm still in the same environment with the people I've been with. I'm not doing anything outside what you guys are telling me. I'm not doing anything that I'm not supposed to be doing."

By July 13, five days after the positive test, Cormier said he was basically back on track with training, though it was a lighter week. Cormier said he was feeling better and got tested three more times between July 12 and July 22. They were all positive. His first negative after all those positives was July 25 -- three weeks before the Miocic fight.

Cormier wants to make it clear that the brief training camp pause and illness did not affect him at all in the fight.

"It didn't kill my preparation," Cormier said. "It really didn't. That's one of the things I want to be vocal about. Stipe Miocic won the fight. This is not an excuse."

His coaches and training partners teased him for wearing the ring, Cormier said, but by the end of the ordeal all of them wanted one.

"They said, 'Muhammad Ali didn't have a f---ing ring,'" Cormier said. "'Tommy Hearns, Marvin Hagler, these guys weren't wearing no ring.' They were like, 'You're tripping on the ring. You're one of the toughest guys in MMA.' They're all wearing Oura rings now."

Cormier retired after the fight and is spending time with his family. His wife, Salina, gave birth to a daughter, Luna Rose, earlier this month. Cormier said he had a lot of people telling him he should share his story, which is why he's talking publicly about it now.

"It did not affect my preparation for the fight at all," Cormier said. "But it was a wild ride."